NSW inmates will no longer be able to smoke while serving time after the state government vowed to outlaw the habit in prisons starting next year.

The attorney general, Brad Hazzard, announced on Wednesday that NSW prisons would be cigarette-free in a year’s time, following similar recent bans in Queensland, the Northern Territory and New Zealand.

Hazzard admitted it would not be an easy transition.

“I know it’s going to be tough because [for] a lot of inmates it’s their social activities,” he told a budget estimates hearing in Sydney.

Hazzard said 80% of inmates smoked, which is about five times higher than the rest of the population.

“Inmates should have the same healthy lifestyle opportunities that those outside enjoy, and take that with them when they return to the community,” Hazzard said.

He said inmates would be given support to give up the habit, and nicotine patches would replace cigarettes as the “currency” in prisons.

“From here on in, I’ll be encouraging inmates to get fit and do circuits, not cigarettes,” he said.

Cancer Council NSW chief executive Jim L’Estrange commended the government for moving to protect non-smoking prisoners and staff from the harmful effects of second-hand smoke.

The prison officers’ union in Queensland has voiced concerns that outlawing cigarettes in jails could lead to a spike in violence.